1. Field of the Invention
This invention relates to an apparatus for detecting the rotation of a motor disposed in a camera.
2. Related Background Art
For the focus adjustment or the like of a lens, it has heretofore been practiced to detect the rotation of a motor for driving a lens barrel by a motor rotation detecting apparatus, and for detecting the position of the lens barrel disposed in a camera.
FIG. 1 of the accompanying drawings shows a camera provided with such a motor rotation detecting apparatus. In this camera, a motor 2 in a camera body 1 is driven, whereby a lens barrel 10 having a lens contained therein is rotated through a train of reduction gears 3, 4, 5, 6, 7 and 8 and a lens barrel gear 9 and is moved back and forth.
Also, an encoder 14 is rotated through speed increasing gears 11, 12 and 13 for rotating the encoder. Slits 14a formed in the encoder 14 are detected by a photointerrupter 15, and pulse signals corresponding to the slits 14a are input from the photointerrupter 15 to a control element 17 via a circuit substrate (board) 16, and the current position of the lens barrel 10 is calculated by the control element 17 on the basis of the pulse signals.
In this camera, the photointerrupter 15 and the circuit substrate 16 are connected together through a flexible print substrate 18, and the photointerrupter 15 is fixed to the camera body 1 with a support member 19 interposed therebetween.
In FIG. 1, the reference numeral 20 designates a cover member, and the reference numeral 21 denotes a window portion for AF.
In such a prior-art camera, however, the fact that the photointerrupter 15 and the circuit substrate 16 are connected together through the flexible print substrate 18 and the photointerrupter 15 is fixed to the camera body 1 with the support member 19 interposed therebetween has led to problems such as increased costs and the bulkiness of the camera.